高比表面介孔LaNiO3负载纳米Au催化剂的研究

Catalytic Performance of Nano Au Catalyst Supported on Mesoporous LaNiO_3 with High Surface Area

分别采用纳米铸型法和溶胶-凝胶法制备了系列LaNiO_3载体,并用沉积-沉淀法制备了系列Au/LaNiO_3催化剂.对催化剂进行了XRD、BET、AAS、TEM和XPS等表征,测试了其对CO催化氧化活性.实验结果表明,纳米铸型法得到的LaNiO_3-NCM具有介孔结构,且比表面积可达126 m2·g-1,以其为载体制备的Au/LaNiO_3-NCM催化剂在30℃条件下将CO完全转化,活性远高于以传统溶胶-凝胶法制备的LaNiO_3-SG为载体的金催化剂. XPS结果表明该Au/LaNiO_3-NCM催化剂表面存在较多的氧化态Auδ+(0<δ<3)和晶格氧,且活性组分Au含量也较高,说明高比表面介孔LaNiO_3载体有利于提高活性组分Au的负载量,从而提高催化剂催化活性.

A series of LaNiO3 supports were prepared by nanocasting and sol-gel method respectively. Au/LaNiO3 catalysts prepared by deposition-precipitation method were characterized by XRD、BET、AAS、TEM and XPS. The catalytic performance for CO oxidation was investigated. The Au/N-LaNiO3 catalyst derived from the nanocasting method showed high activity for CO oxidation,with complete transformation of CO at 30 ℃. The characterization results demonstrated that LaNiO3-NCM support with mesoporous structure from nanocasting method exhibited specific surface area as high as 126 m^2·g^-1. The XPS results implied that the content of oxidized Auδ ＋（O δ 3,or Au＋）,lattice oxygen as well as active species Au was high on the surface of the Au/LaNiO3-NCM catalyst. This result demonstrated that the mesoporous LaNiO3 support with high surface area was beneficial for increasing the loading of Au,thus improved the catalytic activity of the catalyst.